package com.leesche.netdoll.communication.protocol;

import com.leesche.framework.core.codec.HexUtil;
import com.leesche.framework.core.lang.StringUtil;
import com.leesche.netdoll.communication.protocol.decoder.Decoder;
import com.leesche.netdoll.communication.protocol.decoder.DecoderContext;
import com.leesche.netdoll.communication.protocol.decoder.DecoderManager;

public class MessageUtil {

	private static final short[] CRC8_TAB = new short[] { //
			// 0
			0x00, 0x31, 0x62, 0x53, 0xc4, 0xf5, 0xa6, 0x97, 0xb9, 0x88, 0xdb, 0xea, 0x7d, 0x4c, 0x1f, 0x2e, //
			// 1
			0x43, 0x72, 0x21, 0x10, 0x87, 0xb6, 0xe5, 0xd4, 0xfa, 0xcb, 0x98, 0xa9, 0x3e, 0x0f, 0x5c, 0x6d, //
			// 2
			0x86, 0xb7, 0xe4, 0xd5, 0x42, 0x73, 0x20, 0x11, 0x3f, 0x0e, 0x5d, 0x6c, 0xfb, 0xca, 0x99, 0xa8, //
			// 3
			0xc5, 0xf4, 0xa7, 0x96, 0x01, 0x30, 0x63, 0x52, 0x7c, 0x4d, 0x1e, 0x2f, 0xb8, 0x89, 0xda, 0xeb, //
			// 4
			0x3d, 0x0c, 0x5f, 0x6e, 0xf9, 0xc8, 0x9b, 0xaa, 0x84, 0xb5, 0xe6, 0xd7, 0x40, 0x71, 0x22, 0x13, //
			// 5
			0x7e, 0x4f, 0x1c, 0x2d, 0xba, 0x8b, 0xd8, 0xe9, 0xc7, 0xf6, 0xa5, 0x94, 0x03, 0x32, 0x61, 0x50, //
			// 6
			0xbb, 0x8a, 0xd9, 0xe8, 0x7f, 0x4e, 0x1d, 0x2c, 0x02, 0x33, 0x60, 0x51, 0xc6, 0xf7, 0xa4, 0x95, //
			// 7
			0xf8, 0xc9, 0x9a, 0xab, 0x3c, 0x0d, 0x5e, 0x6f, 0x41, 0x70, 0x23, 0x12, 0x85, 0xb4, 0xe7, 0xd6, //
			// 8
			0x7a, 0x4b, 0x18, 0x29, 0xbe, 0x8f, 0xdc, 0xed, 0xc3, 0xf2, 0xa1, 0x90, 0x07, 0x36, 0x65, 0x54, //
			// 9
			0x39, 0x08, 0x5b, 0x6a, 0xfd, 0xcc, 0x9f, 0xae, 0x80, 0xb1, 0xe2, 0xd3, 0x44, 0x75, 0x26, 0x17, //
			// A
			0xfc, 0xcd, 0x9e, 0xaf, 0x38, 0x09, 0x5a, 0x6b, 0x45, 0x74, 0x27, 0x16, 0x81, 0xb0, 0xe3, 0xd2, //
			// B
			0xbf, 0x8e, 0xdd, 0xec, 0x7b, 0x4a, 0x19, 0x28, 0x06, 0x37, 0x64, 0x55, 0xc2, 0xf3, 0xa0, 0x91, //
			// C
			0x47, 0x76, 0x25, 0x14, 0x83, 0xb2, 0xe1, 0xd0, 0xfe, 0xcf, 0x9c, 0xad, 0x3a, 0x0b, 0x58, 0x69, //
			// D
			0x04, 0x35, 0x66, 0x57, 0xc0, 0xf1, 0xa2, 0x93, 0xbd, 0x8c, 0xdf, 0xee, 0x79, 0x48, 0x1b, 0x2a, //
			// E
			0xc1, 0xf0, 0xa3, 0x92, 0x05, 0x34, 0x67, 0x56, 0x78, 0x49, 0x1a, 0x2b, 0xbc, 0x8d, 0xde, 0xef, //
			// F
			0x82, 0xb3, 0xe0, 0xd1, 0x46, 0x77, 0x24, 0x15, 0x3b, 0x0a, 0x59, 0x68, 0xff, 0xce, 0x9d, 0xac //
	};

	public static SimpleMessage decode(String deviceId, byte[] src) throws IllegalChannelMessageException {

		int code = src[8] & 0x3f;

		MessageType type = MessageType.fromCode(code);

		String name = type.getName();

		if (StringUtil.isBlank(deviceId) && type != MessageType.RSP_ID) {
			// logger.error("illegal channel message: {}", HexUtil.encodeHexString(src));
			// return null;

			throw new IllegalChannelMessageException(HexUtil.encodeHexString(src));
		}

		DecoderContext ctx = new DecoderContext(code, deviceId);

		Decoder<?> decoder = DecoderManager.newInstance().decoder(name);

		SimpleMessage o = null;

		if (decoder != null) {
			o = decoder.decode(src, ctx);
		}

		return o;
	}

	/**
	 * CRC8 check sum
	 * 
	 * @param src
	 * @return
	 */
	public static byte crc8(final byte[] src) {

		short crc = 0;

		for (int i = 0, len = src.length; i < len; i++) {
			crc = (byte) CRC8_TAB[(crc ^ src[i]) & 0xff];
		}

		return (byte) crc;
	}

}
